In October, a study was published that predicted that 42 percent of the time, vehicles and CRs are somehow incompatible. The study, “Investigation of Child Restraint System Compatibility in the Vehicle Seat Environment,” by Ohio State College of Medicine’s Injury Biomechanics Research Center, used measurements of 59 current CRs and 61 late model vehicles to evaluate over 3,599 possible CR/vehicle combinations and predict likely incompatibilities. To validate the results, researchers conducted physical installations of 34 of the scenarios.

The researchers measured many aspects of vehicle seating that affects CR installation and then analyzed them to determine the likelihood of incompatibility in a variety of CR installations. For instance:

Over 40 percent of RF CRs were predicted to require assistive tools, such as pool noodles, to achieve a proper installation angle.

In nearly 40 percent of the combinations, it was predicted that the CR’s base would not fit snuggly on the vehicle seat cushion between side bolsters (contours) in the vehicle upholstery.

About a third of the time, the vehicle head restraint was likely to interfere with the proper installation of the CR.

Ten percent of the time, there would not be enough fore-aft depth to install a rear-facing CR properly when the front seat is set to the middle of the adjustment track.

On the brighter side, researchers found minimal instances (less than 2 percent) in which there was likely to be too much CR footprint overhang given the vehicle seat cushion depth, as well as situations in which a FF CR’s tether would be too short to reach the vehicle tether anchor.

The follow-up validation study of physical installations confirmed that the study’s prediction that RF CRs and vehicle seat pan angles would be compatible only about 60 percent of the time was accurate within 6 percent. It also found that the dimensional study’s predictions regarding head restraint interference for FF CRs and fore-aft clearance for RF CRs possibly understated the real likelihood of these problems.

The study’s authors suggest that parents be urged to measure their vehicle seating areas to compare with CR dimensions and to try a store’s display model in their own vehicle before buying.